The joint technical moulding capacity from both companies provides machinery capability from 25 to 1,100 tonnes, including injection, compression and composite moulding services for products weighing from 5 grams to 10 kg.

Prof Richard Lampitt of the National Oceanography Centre told BBC News in 2018 he believed using boats to pull nets and shuttle plastic from ocean garbage patches to ports could have a high carbon cost.

The tech behind these varies according to factors such as width, depth, flow speed and debris type of the river in question - again assessed using AI-powered cameras.

Several years later, he says he remains sceptical about this - but feels far more positive about targeting rubbish in rivers.

The team believes it will have collected 1% of the patch by the end of this year using its current system - but they are scaling up their operations to try to clean up patches faster.

While trying to take on the world's marine pollution problem is undoubtedly tough, and contingent on reduced plastic production and consumption in the first place, Boyan has high hopes for the future.

"We are intercepting plastic in 11 rivers around the world," Boyan said, "but ultimately aim to scale this to all 1,000 heaviest polluting rivers in the world."

While this represents just 0.2% of the 100 million kilograms of plastic contained in the world's largest patch of plastic rubbish, he said it was still worth it: "Everything big starts small, right?"

The new grouping will be led by Shaun Champion of Talisman and Andrew Lawrence, Merriott Plastics. Lawrence said: "We are truly delighted to announce this historic merger; bringing both these industry names together in the service of our customers and for UK manufacturing - while also honouring the legacy tradition that has brought us together."

Champion added: "Throughout the new company our key focus will always be about doing the right thing for our customers. Andrew and I therefore encourage all to call up, get in touch and put this  commitment to the test. We are also exhibiting at Plastics Live 2024, Coventry Arena, June 12-13, 2024 so please make a date to visit our stand then."

Plastic collected by the 800-metre-long (2,600ft) system, the second of its kind developed by the company, is periodically taken to land and emptied for recycling.

Trying to solve the world's ocean plastic pollution problem has been a "long and painful journey" for Dutch entrepreneur Boyan Slat.

But noting the risks of microplastics to the heart of the marine ecosystem, Prof Lampitt said he thought that rather than cleaning up plastic in our seas, "it is really is an issue of stopping the tap and stopping this material getting into the ocean".

Containing a huge build-up of plastic debris ranging from large fishing nets to flake-sized microplastics, it has been one of the main targets for The Ocean Cleanup team.

That legacy tradition is considerable: Talisman (known as LGG Charlesworth until 2018) is more than one hundred years old while Merriott Mouldings began production in the village of Merriott, Somerset in 1938 and ICM in Rochester, Kent in 1947. Each company is a member of the British Plastics Federation and has contributed greatly to the growth and culture of UK Plastics plc.

"There's about 1,000 rivers we need to tackle and five ocean garbage patches, [so] the first few years were really about trying to understand the problem."

Andrew Lawrence remarked that the company is excited to be bringing together the wealth of expertise and knowledge that exists within its businesses, thus creating a formidable team.

The world's biggest area of accumulated ocean plastic, commonly dubbed "the Great Pacific Garbage Patch", is located in the North Pacific Ocean.

The 28-year-old founder of non-profit environmental organisation The Ocean Cleanup has been working on ways to filter plastic waste out of the Pacific Ocean for nearly 10 years.

And The Ocean Cleanup hopes that rolling out 10 of these larger systems in the near-future could clean up to 80% of the North Pacific's plastic debris by the end of the decade.

"I truly believe that with these technologies to clean up the legacy pollution in the ocean and to intercept plastic in rivers before it reaches the oceans, we will actually able to to put ourselves out of business in the not-so-distant future," he added.

Cameras powered by artificial intelligence (AI) are used to continuously scan the ocean's surface for plastic and calibrate the team's computer models, helping them understand which parts of the Pacific area to target.

"When you look at the Great Pacific Garbage Patch, there's some areas that have a very high density of plastic and other areas that are virtually empty," he said.

"The rivers are really the arteries that carry trash from land to sea," Boyan said. "So when it rains, plastic washes from streets into creeks, into rivers, and then ultimately to the ocean."

The newly expanded company will provide customers - particularly in the Midlands, South West and South East - with improved and local product development, manufacture, logistics and technical support.

Changing times, however, require a dynamic response to business that builds on tradition: Shaun Champion Talisman Plastics managing director notes that ‘growth at Talisman in the last 5 years has seen us doubling our turnover and making major investments in people and equipment. This merger enables that rate of growth to continue – providing ‘win-win’ for us - but also great things for our customers, current and future.’

Two UK contract moulders – Merriott Plastics and Talisman – have just combined to create a multi-site, multi-competence business.

Indeed, Merriott Talisman customers in primary group markets such as automotive, electrical, defence and air and fluid movement can now look forward to the many benefits that will flow from the new business which is expected to turnover in excess of £15m sales this year.

"In rivers you really only have one shot at catching the plastic - it just flows by and if you don't catch it, it's guaranteed to enter the ocean," he said.

"If we are continuously cleaning up inside those hotspots, we can of course be a lot more effective in our clean-up operation."

"I cannot think of any way that you can remove these from the natural environment from the ocean without causing massive damage to the food webs, and of course taking an awful lot of energy in order to do it," he said.

The Ocean Cleanup uses a long, u-shaped barrier, similar to a net, that is pulled through patches of rubbish by boats. It moves slowly to try to avoid harming marine life.

Research carried out by the company in 2021 suggests about 1,000 of the world's rivers are the source of 80% of the river-borne plastic contributing to global ocean plastic pollution.